Conventionally, Patent Document 1 (JP2001-001749A corresponding to US 2003/0182955A1) describes regarding an air conditioner for a vehicle that includes an interior heat exchanger and a heater core. The interior heat exchanger is used as a condenser which condenses refrigerant in a heat pump cycle, and the heater core is a heating heat exchanger which heats air by using engine coolant (hot water) as a heat source. The engine coolant is used for cooling an engine which is an equipment attached to the vehicle. The interior heat exchanger and the heater core heat air to be blown into a vehicle compartment of the vehicle, and accordingly, the air conditioner performs a heating operation of the vehicle compartment.
In the air conditioner described in Patent Document 1, the interior heat exchanger is arranged upstream of the heater core in a flow direction of air so that air having been heated in the interior heat exchanger is re-heated in the heater core. A temperature of air to be blown into the vehicle compartment is adjusted by using a flow adjustment valve which adjusts a flow amount of the engine coolant supplied to the heater core.
Hence, in order to perform the heating operation of the vehicle compartment effectively, a temperature of the engine coolant is required to be higher than a temperature of blown air having been heated in the interior heat exchanger of the heat pump cycle. However, if the air conditioner described in Patent Document 1 is used for a hybrid vehicle, waste heat of the engine is too little to be utilized for heating the vehicle compartment via the engine coolant. Therefore, effective heating of the vehicle compartment may be difficult.
Patent Document 2 (JP2006-166639A corresponding to US 2006/0122737A1) describes regarding a power controller for a vehicle, which distributes power from multiple power sources such as, an engine-driven power generator and a battery, to various electric loads attached to the vehicle. The power controller described in Patent Document 2 determines power generating capacities of power generators of the vehicle based on, for example, a total power consumption of the variety of electric loads, such that an operational efficiency of an engine of the vehicle becomes high.